Pump for injecting liquid fuel into internal combustion engines



March 22, 1932. F FEYENS 1,850,926

PUMP FOR INJECTING LIQUID FUEL INTO INTERNAL COMBUSTION ENGINES FiledApril 9. 1928 Patented Mar. 22, 1932 warren stares asst PATENT. @FFHCEFRANQOIS FEYENS, OF BRUSSELS, BELGIUM, ASSIGNOR T0 SOoIE'rE' onnEnALnn'n'runns INDUSTRIELLES, GENERAL RESEARCH CORPORATION, sooIE'rn'ANONYME, or BRUSSELS, BELGIUM, A COMIPANY or BELGIUM PUMP FOR INJECTINGLIQUID FUEL INTO INTERNAL COMBUSTION ENGINES Application filed April 9,1928, $eria1 No. 268,537, and in Belgium April 15, 1927.

The injection of liquid fuel in engines of the Diesel or similar type,must always be effected under very great pressure and this renders itdifiicult to supply the exact quantities required for the small chargesnecessary.

The object of the present invention is'to provide a pump of simple andstrong construction with a positive control for the intake and deliveryor ejecting organs, and allows the pump to be operated at great speedand consequently to be actuated directly by the shaft of the engine.

The pump forming the subject matter of the invention is hereinafterdescribed by way of example, in reference to the accompanying drawingsin which Figure l is a longitudinal section of the pump as whole, and

Figures 2 and 3 are longitudinal sections drawn to a larger scale, inwhich, respectively, the intake and ejecting organs are shown in the twoterminal positions.

The pump body a has an axial bore forming a cylinder in which a piston bis moved downwards by a tumbler lever or tappet k and upwards by aspring The axial bore of the body a has three enlargements or chambersr, s and 2. Tnto the chambers 7' and a open respectively the intake anddelivery pipes p, g, for the liquid fuel; the purport of the thirdchamber 5' is hereinafter described.

The piston Z) comprises a main body, whose lower portion is of smallerdiameter than the upper portion, and has an axial channel m, and twotransverse apertures n and 0' which latter form passages respectivelyfor the intake and the discharge of the liquid fuel. On the reducedportion of the piston there are fitted two sleeves d and c, ofwhich, theformer is fast and within the latter the said reduced portion isindependently slidable, the sleeve 6 acting as a closely fittingobturator or valve. A plunger or brake block 2' bearing against thevalve 0 under the pressure of a spring 72, exerts a braking action andcauses the valve 0 to lag behind when the piston I) receives itslongitudinal motion.

The pump operates as follows aperture 0 is abruptlyterminated throughthe continued upward movement of the sleeve (Z bringing the upper end ofthis sleeve into contact with the lower end of the valve 0 and thereby,as shown in Figure 3, closing the discharge aperture 0. Simultaneously,the upper intake aperture 72 is uncovered and the liquid enters thecentral channel on and fills the lower enlargement or chamber t. Thecontrol tumbler k then becomes operative and begins to depress thepiston 19, while, at the same time, the valve 0, through the action ofthe brake lock 2', will be held stationary. This will cause the intakeaperture 12 to be closed, as in Figure 2, and the liquid fuel, understrong pressure, will be ejected through the aperture 0 into the chamber.9 and thence into the delivery tube g.

The liquid fuel, by filling the lower chain ber It, acts as an elasticcushion to the liquid passing from the centralchannel m, and rendersthe, discharging jet more uniform. At that moment, under the action ofthe spring j, a new return or upward stroke commences, and the beforedescribed cycle is repeated. The quantity of liquid fuel ejected can beregulated by merely varying the stroke of the piston as for example byan adjustable stop or set screw Z, or by more or less choking a by-passin the delivery column.

The pump serves to deliver positively, an accurate charge of fuel, andthe injection takes place exactly at the right moment whatever be thespeed of the engine.

Having described my invention, ll declare that what I claim and desireto secure by Letters Patent is 1. In a liquid-fuel injecting pump, thecombination with a pump body having an incombination with a pumpubodyment of the piston.

adapted to open and close the transverse v apertures alternately.'

2. In a liquid-fuel injectingl pump, the

aving an mlet and an outlet for the el, of a piston longitudinallymovable in the body, a central channel in the piston, two transverseapertures extending through the piston and opening into the centralchannel, and adapted to communicate with the inlet and outlet, a sleevevalve on the piston adapted to open and close the transverse aperturesalternately, and a retarding device engaging the sleeve to cause it tolag'behind during the move 3. In a liquid-fuel injectin pump, thecombination with a pump body having an inlet and an outlet for the fuel,of a piston provided with a reduced portion and with en; larged endportions and longitudinally movable in the body, a central channel inthe piston, two transverse apertures extending through the piston andopening into the central channel, and adapted to communicate with theinlet and outlet, and a sleeve valve mounted on the reduced portion ofthe piston with freedom of movement between the two enlarged portionsthereof, and displaceable longitudinally in the pump body under theaction of said piston, said sleeve valve being adapted to open and closethe transverse apertures alternately, said ump. body being provided withthree chambers, into one of which opens the inlet and one of the transverse apertures, into another opens the outlet and the second transverseaperture, and with the third of which the central channel is in opencommunication.

4. In a liquid-fuel injecting pump, the combination with a pump bodyhaving an inlet and an out-let for the fuel, of a piston longitudinallymovable in the body, a central channel in the piston, two transverseapertures extending through the piston and open.-

inginto the central channel, and adapted to communicate with the inletand outlet, a sleeve valve on he piston movable relatively thereto toopen and close the transverse apertures alternately, said pump bodybeing provided with three chambers, into the upper of ,which opens theinlet and one of the transverse apertures, into the second of whichopens the outlet and the second transverse aperture, and in the lowestof which nearest the outlet, plunges the lower end of the piston, saidlowest chamber being in open' communication with the said centralchannel, and a retarding device engagin the sleeve to cause it to lagbehind the piston during its longitudinal movement.

In witness whereof I have afiixed my sig- 7 I nature hereto.

QOIS FEYENS.

